1. Field of the Invention
The present invention relates to heat exchange units. More specifically, the present invention relates to a subassembly incorporating a fan orifice, top cover and a grille as well as a method of assembly thereof.
2. Prior Art
Wound fin heat exchangers are well known in the refrigeration and air conditioning field. A wound fin heat exchanger consists of a tube having a fin material wrapped about the tube in heat exchange relation therewith to promote heat transfer between the fluid flowing through the tube and a separate fluid flowing over the tube. Utilization of this type of heat exchanger, wound fin, has been found to be both cost effective and to provide the appropriate heat transfer with a minimum of tube length. A type of wound fin heat exchanger includes slit fin tubing wherein a sheet of fin material is slit laterally and then rolled to a generally U-shaped arrangement such that the non-slit portion is wound against the tube and the slit portions extend outwardly therefrom.
To make advantageous use of wound fin heat exchangers it is necessary that the heat exchanger be configured to optimize heat transfer. Once the appropriate configuration is ascertained the wound fin tubing should then be maintained in that configuration for the life of the heat exchanger. It has been found that the cylindrical configuration having the air drawn inwardly through the cylindrical heat exchanger is a preferred design.
It has additionally been ascertained that various support arrangements for securing wound fin heat exchangers may also be used to support the remaining assemblies of the heat exchange unit. More particularly, the incorporation of a fan orifice defining a void and a top cover for encasing the annular orifice such that a space is provided therebetween wherein electrical controls may be mounted has proved advantageous. Additionally, this assembly may be provided such that a grille is secured between the fan orifice and the top cover and a fan motor coacting with the fan orifice surface may be suspended from the grille.
The herein described apparatus not only serves to provide a fan orifice but also provides an enclosed area for securing electrical components and acts to integrate the heat exchanger assembly with the wrapper of the unit and to provide an aesthetically pleasing arrangement of components.